I was sending information letter to the club subscribers(total 225 emails) using Gmail account. I keep them in 3 mailing lists: 2 with 95 emails and 3rd with remaining(GMail limit recipients to 100 per email). The first list was rejected with the following (not very specific) message.
Delivery to the following recipient failed permanently: email address
Technical details of permanent failure:
Message rejected. See https://support.google.com/mail/answer/69585 for more information.
But the second list with the same size was successful.
Additional annoyance was that “delivery failed” notifications were received slowly within 5 minutes, and initially I didn’t understand which group (or emails from both groups) were rejected.
The simple workaround to split big list in 3 smaller mailing lists one was successful.
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